Our third example is the Ohta-Kawasaki equation [1]}
\({\left\lbrace \begin{array}{ll}u_t = - u_{xxxx} - (\psi _\lambda (u))_{xx} - \lambda _3 u, &\quad \text{for } x\in [0,\pi ],\\u_x(t,0)=u_x(t,\pi )=0, \\u_{xxx}(t,0)=u_{xxx}(t,\pi )=0,\\\int _0^\pi u(0,x) dx =0 ,\end{array}\right.}\) 
